From 6668ed271eaefaa63e686bdfbedaeb7b8e492722 Mon Sep 17 00:00:00 2001 From: Kumar Kartikeya Dwivedi Date: Fri, 4 Sep 2026 10:43:19 +0200 Subject: selftests/bpf: Reject graph kptr use after RCU unlock Add a sleepable verifier test that loads a graph-node local kptr in an explicit RCU read-side critical section, then passes its node to bpf_rbtree_remove() after the section ends. Before the verifier fix, the stale NON_OWN_REF flag makes the node look like a live borrowed reference and the program is accepted. After the fix, the pointer is demoted without NON_OWN_REF and the graph kfunc argument is rejected. Also exercise a graph kptr loaded while a spin lock provides implicit RCU protection. The pointer must be invalidated when the lock is released, which guards the required ordering between non-owning-reference invalidation and RCU demotion. Update the existing fault-protected load test state description. The post-unlock pointer no longer carries NON_OWN_REF, but remains readable because the load is rewritten to use BPF_PROBE_MEM. Signed-off-by: Kumar Kartikeya Dwivedi Link: https://lore.kernel.org/r/20260904084325.52250-7-memxor@gmail.com Signed-off-by: Alexei Starovoitov --- tools/scripts/Makefile.arch | 46 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 46 insertions(+) create mode 100644 tools/scripts/Makefile.arch (limited to 'tools/scripts/Makefile.arch') diff --git a/tools/scripts/Makefile.arch b/tools/scripts/Makefile.arch new file mode 100644 index 000000000..eabfe9f41 --- /dev/null +++ b/tools/scripts/Makefile.arch @@ -0,0 +1,46 @@ +# SPDX-License-Identifier: GPL-2.0 +HOSTARCH := $(shell uname -m | sed -e s/i.86/x86/ -e s/x86_64/x86/ \ + -e s/sun4u/sparc/ -e s/sparc64/sparc/ \ + -e /arm64/!s/arm.*/arm/ -e s/sa110/arm/ \ + -e s/s390x/s390/ -e s/parisc64/parisc/ \ + -e s/ppc.*/powerpc/ -e s/mips.*/mips/ \ + -e s/sh[234].*/sh/ -e s/aarch64.*/arm64/ \ + -e s/riscv.*/riscv/ -e s/loongarch.*/loongarch/) + +ifeq ($(strip $(ARCH)),) +override ARCH := $(HOSTARCH) +endif + +SRCARCH := $(ARCH) + +# Additional ARCH settings for x86 +ifeq ($(ARCH),i386) + SRCARCH := x86 +endif +ifeq ($(ARCH),x86_64) + SRCARCH := x86 +endif + +# Additional ARCH settings for sparc +ifeq ($(ARCH),sparc32) + SRCARCH := sparc +endif +ifeq ($(ARCH),sparc64) + SRCARCH := sparc +endif + +# Additional ARCH settings for loongarch +ifeq ($(ARCH),loongarch32) + SRCARCH := loongarch +endif + +ifeq ($(ARCH),loongarch64) + SRCARCH := loongarch +endif + +LP64 := $(shell echo __LP64__ | ${CC} ${CFLAGS} -E -x c - | tail -n 1) +ifeq ($(LP64), 1) + IS_64_BIT := 1 +else + IS_64_BIT := 0 +endif -- cgit v1.3.1